Effects of liming on the nutrition, vigor, and growth of sugar maple at the Lake Clair Watershed, Québec, Canada

In the 1980s, sugar maple (Acer saccharum Marsh.) dieback was observed across its range in Quebec. In spite of the recovery of the majority of stands during recent years, some have continued to show signs of dieback progression. At the Lake Clair Watershed experimental station, a study was undertaken to evaluate the effect of liming on the nutrition, vigor, and growth of sugar maple in an acid soil, poor in available Ca and Mg. A completely randomized experiment was established and selected sugar maples were treated in 1994 with dolomitic lime in amounts of 0, 0.5, 1, 2, 5, 10, 20, or 50 t·ha-1. Four years after the lime application, improvements in foliar concentrations of N, P, Ca, and Mg were noted. Liming increased the radial growth of sugar maple by 45% for rates from 1 to 10 t·ha-1 and by 90% for rates of 20 t·ha-1, compared with the control trees. The beneficial effects of lime on dieback appeared only very slightly at the third and fourth years after treatment. The negative impact of liming on sugar maple K nutrition could be mitigated by application of potassium sulphate.